Striking-pin for piston-hammer rock-drilling engines.



J. G. LBYNER. v STRIKING PIN POR PISTON HAMMER GK DRILLING ENGINES.

APPLICATION FILED APB.3, 1905.

Patented 0013.20, 1908. 2 SHEETS-SHEET 1.

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3m m WNW. n m@ m -Mmmm A IN w SM mgm NQ m ww mm J. G. LEYNER. STRIKING PIN FOR PISTON HAMMERV ROCK DRILLING ENGINES.

' APPLICATION FILED A?B.3, 1905. 901,538. Patented 0ct.2o,19o8. 2 SHEBTS-SHBET 2.

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WW JJM w? a e 5 w Lw Q r a JOHN GEORGE LEYNER, OF DENVER, COLORADO.

STRIKING-PIN FOR PISTON-HAMMER ROCK-DRILLI'NG ENGINES.

Specification of Letters Patent.

Patented Oct. 20, 1908.

Application sied April s, 1905'. serial No. 253,409.

To all whom it may concern:

Be it known that I,.JoHN GEORGE LEYNER, a citizen or` the United States of America-residing in the city and county of Denverand State of Colorado, have invented a new and useful Striking-Pin for PistonIIammer Rock- Drilling Engines, of which the following is a specification.

My invention relates to a new invention which I term a hammer striking pin for fluid pressure, for rock drilling engines, and that is especially adapted for the piston hammer type of rock drilling engines, and that I especially use in vconnection with my drill bit rotating mechanism for rock drilling engines embodied in my Letters Patent No. 796,081, dated August 1, 1905. v

The mechanism is illustrated in the accompanying drawings, in which,"

Figure 1 is a plan view of a rock drill'embodying my invention; Fig. 2 is a central, vertical, lon` itudinal sectional view through the same. Fig. 3 is an elevation ofthe front end of the drilling-engine. Fig. 4 is an elevation ofthe front end of the drilling engine, with the front cylinder head removed. Fig. 5 is a' transverse, vertical, sectional view on the line 5-5 of Fig. 2. Fig. 6 is a plan view of the sleeve through which the feed screw passes ,and which has an integral gear wheel at one end. Fig. 7 is a transverse, sectional view of thesame, on the line 7-7 of Fig. 6. Fig. 8 is a sectional view in perspective, of the strikingepin-holdin' buffer sleeve.V Fig. 9 is a side elevation of t e drill-strikingv pin. Fig 10 is a side elevation 'of the drill-holding gear chuck. Fi I. 11 is a side elevation of the Jfront cylin er head. Fig. 12l is'a rear view thereof. And Fig. 13 isa perspective View ofthe drill-bit.

Similar letters of reference refer to similar parts throughout the several views.

Referring to the drawings: The numeral 1 designates the c linder of my rock drilling en ine. This cylinder is provided with an axial bore of two diameters, 2-and 3, the largest of which, 2, extends into it from its rear end, for about one-half of thelength of theV piston hammer s stroke, where it terminates in a square shoulder, 4, at the beginning of the smaller bore, l3, which continues from the shoulder to the end of the pistons portion of the cylinder. The entrance to the rear end of the c* linder bore is threaded, and receives acjylin er head, 5, which comprises a lange portion 6, with a projecting hexagon nut 7, on its outside,A and a hub portion on its inside. The huleV portion is threaded to screw into the threaded bore of the cylinder until! the ilange bears tightly against the end of the cylinder.-

At a short distance from the rear end of the cylinder I form onthe cylinder a transverse cylindrical boss portion '8, in which is formed a-circular air inlet aperture 9, the entrance of which is threaded to receive the threaded connecting end of the hose 10, which leads to l a supply of compressed air.` rIhe air inlet aperture connects with a circumferential recess, 12, formed in the periphery of the bore of the cylinder, whic forms the air inlet port of the cylinder.

Ad]acent to the shoulder 4 and in the larger bore of thejcylinder, a circumferential air inlet port, 13, isalso formed, and the port 12- is connected to the port 13 by ports 14, that are drilled into the rearend of the'shell of the cylinder in axial alinement with the axis of the cylinder, and in position to intersect the port 12 and to extend to and intersect the port 13, which is located in a circum A.

ferential rib 8B, that surrounds over` the port 13.

-The entrances to vthe port holes 14 are tightly plugged after they are drilled. At the front end portion et the smaller diameter of the piston s bore a circumferential exhaust port 16 is formed in the cylinder. This ex aust por-t is open to the atmos -here through an exhaust aperture 1-7, w rich extends through the bottom of the shell of the cylinder into it. In the bore of the cylinder I reciprocally mount a fpiston hammer 18, the peripheral surface o which is made in two diameters, 19 and 20, to fit the two diameters of the cylinders bore. The piston hammer is provided with an axial bore 21,- which extends into it from its rear end to within a short distance from its front end. This piston is provided, adjacent to 'itsl rear end, with radial port holes 22, which extend from the exterior face of the piston hammer through its shell. These ports are preferably arranged so that a part of them will radiate at substantially a right angle to the axis of the hammer, andthe rethe cylinder los` mainder will stand at an obtuse forward angle from the interior` base of the hammer, and

they are also preferably arrangedr so that.

their entrances within the bore of .the hamsA mer are arranged in an alternatingfzigzagx circumferential line. The forward end of the viston hammer at the inner end of its axial ore is provided with a radialrow of port holes, 23, that extend from the interior bore through the shell of the hammer.

end of the cylinders piston hammer bore, an axial bore 24 is formed, which is larger in diameter'than the .bore of the hammer, and at the end of the bore 24, astill larger bore 25 is formed in the linder that extends to its front or drill-bitaiolding end substantially square shoulders 24A and 25A are formed between these three bores of the cylinder. The corners of the shoulder 25A are, however, i5 preferably. rounded. In the bore 24, I place a steel bu'er sleeve, 26. This sleeve lits loosely but snugly, in the bore, and normally against the shoulder 24A, formed between the piston hammers bore and the bore 24, and on the outer end of this sleeve an enlarged collar portion 27, is formed, which iits normally in the large end `bore 25, against the shoulder 25A formed between the bore 24 and the bore 25'. Against the forward end of the steel. buffer sleeve, I place a rubber buffer ring 28, and against this rubber buffer ring I place 1 a steel washer 29. This steel washer and the rubber buffer ring contain large axial aper tures through which projects loosel one end of a drill-bit holding chuck or s eeve, 30, 'which projects at one end into the end of the cylinder and through this steel washer and rubber buffer ring and also loosely into the u sleeve 26, for a short distance of the sleeves length. The opposite end of the chuck projects forward'beyond the end of the cylinder, 'and is inclosed by a hub7 30A, formed on the lfront cylinder head 31. The opposite sides ofthe front end of the cylinder are provided with lugs 32, to whch one end of studs 33 are threaded.

i The front cylinder head is provided withlu lportions, 33A, that are provided with ho es that fit over the studs, and the nuts, 34, are threaded to the free ends of the studs, which profeet through the holes in the cylinder head. A

The drill-bit holding chuckv is provided at about the central portion of its length with a 5D gear,.35, which is formed preferably by an i enlarged integral portion, in the peripheral surface of which the teeth of the gear are formed. This gear portion of the chuck fits l snugly but rotatably between the front cylinder head and the steel washer. This gear, however, is not large enough in diameter to extend to the inner peripheral surface of the cylinder, and l iill up the space between the outside diameter of the gear and the inner peripheral surface of the cylinder by a ring shaped hub ortion, 31A, that is formed in tegral with t e front cylinder head and that projects from its inner side into the end of the c linder between the gear and the inner perip ery of the cylinder. A portion of the At the under side of this hub is cut away to allow the gear, 35, to mesh with a gear placed below it, as will be more fully explained here,- inafter.

The steel buffer sleeve is provided at its end facing the piston hammer with an axial l aperture, 35, of smaller diameter than the aperture in its opposite end, into whiclithe drill holding chuck extends, and in this a erture 36, l iit loosely the front end of a .iar 75 dened steel pin, 37, the opposite end of which fits loosely into the adjacent end of the drillbit holding chuck. Upon the body of this pin, l form a circumferential collar, 38, which tits loosely in the larger axial a )erture of the steel butler sleeve, and normally rests against the shoulder formed between the larger aperture of this buff er sleeve and the smaller aperture 36. The drillbit-holdingchuck does not extend into the larger aperture of the steel buiier sleeve to the collar formed on the steel pin, but stops at a short distance from it, and a compensating s )ace is left within the steel butler sleeve and between the end of the chuck and the collar of the striking pin. rThis steel pin, 37, l term the striking pin, and the Aend of this striking pin thatv rejects through the aperture 36, in the steel uffer sleeve, projects beyond the sleeve a short distance into the reciprocal path of the piston hammer, and" the compensating movement of this pin is to permit the striking pinto be driven forward when. it is struck by the hammer Within the drill-holding chuck.

rlhe rock cutting drill-bit, 39, is referably formed of what is known as cruci orm steel, and the shank'of this drill-bit consists of a bar of any predetermined length of this character of merchantable steel, and the rock cutting li )s are formed upon its outer end in the usua manner. The chuck is provided with an axial aperture, 37A, which is cruciform to correspond to the shape of the drill, and the shank end of the drill projects loosel ii'ito the drill-holding chuck and this shank end is not mani ulated .in any way. It is free from shoul ers'or projectionae and it consists simply of the natural end of this bar of steel projecting loosel into the drill-holding chuck and against t e striking pin, and into the short compensating or reciprocal movement of the striking pin. The drill-bit is-held in operative relation to the rock in whichfit is drilling by roperly feeding the cylinder forward in suc i a manner that the s ank end of the drill-bit is held against the en d of thestriking pin and the striking ins collar is held against the shoulder forme( between its smaller and larger a iertures. Then when the piston hammer strikes the striking pin, the blow is imparted by the striking pin to the end of the drill-bit, and it is driven into the rock and the compensating movee ment of the striking in allows forward feedi ing movement of stri ring pin to compensate 130 lio for the blow of the iston driving the cutting oints of the drill it into rook, and also for ailure on the part ofthe o ierator to feed the cylinder to hold the drillrit close up to. or

with slight pressure against the rock.

' A depending lu portion, 40', is formed on.

the cylinder, whic contains an aperture, 4l, through it, and a counter-bore, 42, is also formed in it concentric to the aperture 41. T-In this counter-bore, l place a gear 43, the teeth of-which mesh with the teeth of the drill holding chuck ear, 35. This gear 43 is i provided with a hu portion 44, that fits rotatably in the aperture through thede end- ?115 ingl lug 40, and from this hub a long s eeve 45,y extends forward under the cylinder to ,cl-osev to a. nut 46, which is secured in a depending lug 48forrned on the rear end of the cylinder. ThisV nut 46.is threaded and a feed screw 47 is rotatably threaded to it, and

ameter and the metal is swaged or driftedl away from the op osite side o the inner peripheralsurface o the wall of this reduced axial aperture by drifts or swages, in such a manner as to leave two feather keys 49 depending from the inner periphery of the aperture. 'These feather keys are arranged and adapted to itslidablv inthe key Ways in the opposite sides of thefeed screw, so that when the' feedv screw is rotated the sleeve and gear" will be rotated with it, and will also feed 40 Il along its length as the cylinder is moved, @which movement of the cylinder is caused by the opposite or outer end of the feed screw being secured rotatablyto the head portion, 49A, of rearwardly extending arms 50, which are secured at their innerend to a supporting shell 51. This supporting shell is provided with slide ways 52 on its opposite sides, and the cylinder is provided with guide ways 53, which are arranged and adapted to fit and v50 slide in the slide ways of the supporting shell.

The bottom of the shell is provided with an inverted fan-tail or dove-tailed shaped circular hub, 52 which is adapted to be clamped by a stoping bar chuck in a well known 55 manner. The outer end of the feed screw is provided with a crank handle .54, which is secured to the feed screw in such a manner that the feed screw is rotatably journaled to the head portion 49^ of the arms 50 against i longitudinal movement. The front cylinder head de ends down over the gear 43 and is provider with a hub portion through which the feedscrew projects loosely.

The sleeve 45 is provided with. axial a er- 654 tures, 45^, which are placed through its s ell `opposite-the exhaust port 17, which permit the exhaust air to enter the sleeve and keepy the screw free from dust and lubricate it.

On the rear end of the vcylinder l. form or secure by any suitable l.means an arm 55, 70 which is positioned to'stand over the slide ways of the shell, and on the op osite end of' the shell -in the path of this arm Vform or secure a projecting abutment stop 56, against which the arm strikes when the cylinderis fed forward in the shell as far as it should be in the shell, and which limits the operative feeding stroke of the cylinder, and prevents the cylinder being fed .too far forward in the shell. y The operation is as follows: When the screw is rotated by the crank, the cylinder is `fed to and fro in its su porting shell, as the nut 46, which is attac ied to the cylinder',

feeds to and fro de ending on which way the feed screw is turne and the sleeve 45 land its ar 43 turn with the feed screw, being held y its feather keys, and they also slide alongA t'ieifeed screw with theV c linder. p As the gear 43 is rotated by the fee screw, it rotates 90 the drill holding chuck gear fand the drill holding chuck rotates the rock cutting drillsbit. The piston hammer and ports operate in the following manner: Assuming the piston to be at the end of its forward stroke in the cylinder as shown in Fig. 2, the compressed air flows from its source of supply through the hose 10 into the inlet port 12 and vthrough the longitudinal port i4 to the port 13, and entering the c d'mder between the 100 shoulder 4 of the cylin er and the shoulder 20A of the piston hammer, moves the piston backward to the rear end of its stroke in the cylinder, and when the ports of the pston. hammer pass the yinlet port 12 the air rushes 105 from the inlet port into and through the plurality of radial ports 22 into the interior of the piston hammer and to the rear end, cushioning it just before it strikes the cylinder head and starting it back and throwing it for- 1 1.0 ward and impinges it with great velocity against the end of the striking pin. as the air flows into the interiorof the piston hammer in much greatervolume than against its shoulder through the port holes 22, when it reaches the forward end of its stroke, its exhaust ports register with the exhaust port 16 and the air in the interior of the )iston hammer flows out tothe atmosphere t rough the'exhaust ports23. The air then again-l enters the inlet port 9, and the reciprocal stroke is repeated. The piston hammer strikes the striking pin withy great ra idity, causing it to strike the end of the roc i cuttin drill bit each time it is struck by the piston aminer, and the operation rotates the crank handle and the feed screw and feeds the c dinder for* ward in its supporting shell just fiast enough to keep the dri l-bit in operative relationto rock. In case, however, the drill-bit is so 130 loosely held in the drill chuck that the striking pin does not strike it or is not in the drill chuck, the striking pin is then driven against the adjacent end of the drill chuck, andthe piston hammer strikes against the end of the steel buffer sleeve, which cushions against the, rubber buiiervand the steel washer and the gear and cylinder head. -The rubber buffer cushions the blows, however.

It will be seen by the above that by the use of the striking pin I am enabled to use rock cutting drill bits having straight natural bar shanks of any kind or character oi cross section, without doing any work on them or providing them with colla-rs or shoulders or lugs or other members that are intended to bear against the end of the cylinder and define the distance the striking end of the shank shall extend into the cylinder; ,thus enabling me to do away or dispense with all that character of work and greatly cheapen the cost of the rock cutting drill-bits. *The drill bits are thrown around the floor of shafts, stopes, and tunnels, and get covered with grit, sand, and mud, and this striking pin, taken in connection with the steel sleeve, also prevents this sand, mud, and grit from working into,

the cylinder of the piston hammer.

Although I preferably use cruciiorm steel, still my invention contemplates the use of an form of cross-section rof any merchantabe tool steel, used for cutting rock,` as round, square, hexagon, triangular, ribbed,

. or cross-ribbed, or of any polygonal form.

Having described my invention, what I claim as new and desire to secure by Letters Patent, is

1. In a rock drill, a drill-bit, a hammer piston, a striking pin inserted therebetween and adapted to receive and impart blows of said hammer piston to said drill-bit, and a buffer device arranged to receive direct blows from said hammer piston when the striking pin is in its lowermost position.

2. In a rock drill, a drill-bit, a hammer piston, a striking pin inserted therebetween and adapted to receive and impart blows of said hammer piston to said drill-bit, and an elastic buffer device arranged to receive direct blows from said hammer piston when the striking pin is in its lowermost position.

3. yIn a rock drill, a drill-bit, a hammer piston, a striking pin inserted therebetween and adapted to receive and impart blows of said hammer piston to said drill-bit, and an independently-mounted buffer device arranged to receive direct blows from said hammer' piston when the striking pin is in its lowermost position.

4. In a rock drill, a drill bit, a striking-pin, a hammer-piston for striking the strikingpin, and an elastically mounted buffer device arranged to receive the inoperative blows of said hammer-piston.

5. In a motive iluid hammer-piston rock drilling engine, the combination with the c linder and the hammer-piston, of a drillit holding chuck mounted 1n said cylinder, .provided with an enlarged portion, a steel buffer sleeve mountedin said cylinder in the reciprocal ath of said hammer-piston, and arranged) to fit over the end of said chuck, a resilient buffer ring and a steel washer mounted on said chuck between said steel buiier sleeve andsaid enlarged portion of said chuck, said buffer sleeve having an axial aperture of two diameters, arranged to form a shoulder in the front end of said sleeve, a pin reciprocally mounted in said sleeve, and arranged to project normally beyond the said sleeve into the reciprocal path of said hammer-piston, a collar on said. pin arranged to have asliding movement between thel shoulder in said steel buer sleeve, andthe ad'acent end of said chuck, and adapted to eiine the reciprocal compensating movement of said pin, relative to the reci rocal strokes of said hammer-piston, and a rill-bit adapted to be supported by said chuck against said pin, substa" tially as described. v

6. In a rock drill, the combination oi a cylinder and a hammer-piston of a drill chuck, a.

drill-bit, and a buffer device between the drill chuck and said'hammer-piston, and a striking-pin, reciprocally vmounted between said hammer-piston, and said drill-bit, and adapted to receive and impart the blows of said hammer-piston to the drill-bit, substantially as described.

7. In a rock drill, the combination of a c linder, a hammeriston, a drill chuck, an a drill-bit, with a rill-bit striking-pin interposed between said hammeriston and saidl drill-bit, and adapted to receive the blows of said hammer-piston, and impart them to said drill-bit, and a steel sleeve, and a resilient buiier device ada ted to cushion the inoperative blows of saidhammer-pistcn.

8. In a Huid-pressure rock drill, a cylinder, a non-revoluble hammer piston, a drill-bit, a separate striking pin, and arevoluble drillchuck.

- 9. In a rock drill, a cylinder', a non-revoluble hammer piston, a striking pin, a revoluble drill-chuck, and a drill-bit reciprocable in but rotatable with said chuck.

10. In a rock drill, a cylinder, a non-revoluble hammer piston', a drill-bit, -a separate striking pin, and a revoluble drill-chuck re-` ceiving said drill-bit and striking pin.

11. In a rock drill, a cylinder, a hammer piston', a striking pin having a circular end. a drill-bit having an angular shank, and a revoluble drill-chuck having a circular op ening receiving said striking pin and an angular-opening receiving said drill-bit.

12. In a rock drill, a cylinder, a non-revoluble hammer piston, a striking pin, a revolulole drill-chuck, and a buer arranged' to receive the inoperative blows of said hammer piston.

'13. In a rock drill, a cylinder, a non-revo- 5 luble hammer iston, a striking pin, a revolnble drill-chuc i, and an annular buffer surrounding said strilingvin and arranged to receive the inoperative lows of said hammer piston. I 10 14. In a rock-drilling engine, a revoluble,

non-reciprocable chuck, a drill-bit mounted to rotate with and reciprocate in said chuck, a reciprocable striking-pin, and means for im-l parting a blow to said striking-pin.

In testimony whereof I afx my signature 15 in presence of two witnesses.

JOHN GEORGE LEYNER. Witnesses:

JOHN A. FARWELL, R.L. BROWN. 

